Hoya flavida P.I. Forster et D. J. Liddle 1993
Type description:
In Austrobaileya 4/1 (1993) 53-54. P. I. Forster & D. J. Liddle. Hoya flavida P.I. Forster et D. J. Liddle, sp. nov. affinis H. anulatae Schltr. a qua foliis succulentioribus, corolla campanulatirotata lutes vel flavida lobis ovatis, et lobis coronae staminalis margins exteriors rotundato differt. Typus: cultivated at Emerald Creek near Mareeba (ex plant collected on Mt. Gallego, Guadalcanal Province, Solomon Islands), 24 February 1992, D. J. Liddle IML118 (holo: BRI (1 sheet + spirit)).
Epiphytic fleshy vine to several meters long, latex white. Stems cylindrical, glabrous; internodes up to 120 mm long and 2.5 mm diameter. Leaves glabrous, petiolate; lamina elliptic-ovate, up to 140 mm long and 45 rum wide, discolorous, secondary veins 4 per side of midrib just visible on both surfaces, tertiary venation obscure; upper surface dark green; lower surface pale green; tip acute to short acuminate; base cuneate; petiole grooved along top, 10 - 12 mm long and c.1.5 mm diameter; colleters 2, at lamina base. Cyme umbelliform to racemiform, up to 140 rum long; peduncle up to 135 mm long and 1.5 mm diameter, glabrous; bracts ovate, 0.3‑0.4 mm long, 0.3- 0.4 mm wide. Flowers 3‑4 mm long, 10-15 mm diameter; pedicels 15‑22 mm long, c. 1 mm diameter, glabrous. Sepals lanceolate, 1.2‑1.4 mm long, 0.5‑0.6 mm wide, glabrous. Corolla campanulate‑rotate, yellow to yellow‑pink, externally glabrous, internally with dense short white trichomes that are uniformly distributed except for on the lobe edges where slightly dense but not forming a conspicuous band; tube 3‑4 mm long, 7‑8 mm diameter; lobes ovate, 5‑5.5 mm long, 4.5‑5 mm wide. Staminal corona 2.8‑3 mm long, 5.5‑5.8 mm diameter, inserted on column flush with corolla, yellow‑pink; each lobe c. 2.5 mm long, 2.5‑2.8 mm high, 1.3‑1.5 rum wide, outer edge somewhat rounded‑obtuse and not upraised above the level of the style‑head, inner edge acute. Staminal column c. 2 mm long and 2.5 mm diameter; anther appendages lanceolate, c. 0.8 rum long and 0.5 mm wide; alar fissure c. 1 mm long. Style‑head c. 1 mm diameter. Pollinaria c. 0.32‑0.36 mm long, 0.27-0.32 mm wide; pollinia oblong, 0.29‑0.33 mm long, 0.12‑0.13 mm wide, with pellucid germination mouth on outer edge; corpusculum oblong, 0.09‑0.11 mm long, 0.05‑0.06 mm wide; caudicles winged, c. 0.09 mm long and 0.05 mm wide. Fruit and seed not seen. Fig. 2.
Specimens examined: Papua New Guinea. Bougainville Province: South slopes of Crown Prince Range, Apr. 1936, Voyce D2 (K). Cultivated. cultivated at Emerald Creek near Mareeba (ex plant collected on Mt. Gallego, Guadalcanal Province, Solomon Islands). Feb. 1992, Liddle IML423 (BRI).
Distribution and habitat: Known only from Bougainville and Guadalcanal Islands in the Solomon Islands chain. Plants occur as epiphytes in lowland rainforest. In addition to the plants in cultivation from Mt. Gallego, we have also collected plants from the Lungga River area on Guadalcanal that are probably referable to this species; however, they have yet to flower for us to be sure.
Notes: H. flavida is a free flowering plant that is now reasonably well spread in cultivation as H. sp. 'Mt. Gallego'. It is probably allied to H. anulata Schltr. from mainland New Guinea and Australia (Forster & Liddle 1990, 1992) but differs from that species in the more succulent leaves, the yellow or yellowish campanulate-rotate corolla with ovate lobes; and the staminal corona lobes with rounded outer edges.
Etymology:The specific epithet alludes to the yellowish corollas.
Acknowledgments:
Figures 1 and 2 were drawn by W. Smith (BRI). Our visit to Papua New Guinea, enabling a visit to the LAE herbarium, was made possible by the award of a Christensen Research Institute Fellowship and we are grateful to M. Jebb, Director of that institute for his support. G. Stocker was of great assistance with our visit to Lae. L. A. Craven (CANB) kindly provided Latin translations of the diagnoses. Plants or information on localities were supplied by G. Dennis, B. Ghen and the late P. Tsang. The Directors/Curators of A, B. BM, BO, BSIP, CANB, K, L, LAB, MICH, SING, NY, W and WRSL allowed access to collections in their care, either on loan or on visits to their institutions.
References:
Forster, P. l. & Liddle, D. J. (1990). Hoya R. Br. (Asclepiadaceae) in Australia ‑ an alternative classification. Austrobaileya 3: 217‑234.
— (1991). Variation in Hoya australis R. Br. ex Traill (Asclepiadaceae). Austrobaileya 3: 217-234..
— (1992). Taxonomic studies on the genus Hoya R. Br. (Asclepiadaceae) in Papuasia, 1-5 Austrobaileya 3: 627- 641.
Translation: like Hoya anulata Schlechter from which it differs by its more succulent leaves, campanulate corolla pale yellow or yellow ovate lobes, and with the staminal coronal lobe exterior margins rounded.
In Hoya Section Acanthostemma (Blume) Kloppenburg (1994) 43-44. R. D. Kloppenburg. Hoya flavida P. I. Forster et D. J. Liddle, sp. nov. affinis H. anulata Schltr. a qua foliis succulentioribus, corolla campanulatata lutea vel flavida lobis ovatis, et lobis coronae staminalis margine exteriore rotundato differt. Typus: cultivated at Emerald Creek near Mareeba (ex plant collected on Mt. Gallego, Guadalcanal Province, Solomon Islands, 24 February 1992, D. J. Liddle IML 118 (holo: BRI ( 1 sheet + spirit)).
Epiphytic fleshy vine to several meters long, latex white. Stems cylindrical, glabrous; internodes up to 120 mm long and 2.5 mm diameter. Leaves glabrous, petiolate; lamina elliptic-ovate, up to 140 mm long and 45 mm wide, disclorous, secondary veins 4 per side of midrib just visible on both surfaces, tertiary venation obscure; upper surface dark green; lower surface pale green; tip acute to short acuminate; base cuneate; petiole grooved along top, 10-12 mm long and c. 1,5 mm diameter; colleters 2, at lamina base. Cyme umbelliform to racemiform, up to 140 mm long; peduncle up to 135 mm long and 1.5 mm diameter, glabrous bracts ovate, 0.3-0.4 mm long, 0.3-0.4 mm wide. Flowers 3-4 mm long, 10-15 mm diameter; pedicels 15-22 mm long, c. 1 mm diameter, glabrous. Sepals lanceolate, 1.2-1.4 mm long, 0.5-0.6 mm wide, glabrous. Corolla campanulate-rotate, yellow to yellow -pink externally glabrous, internally with dense short white trichomes that are uniformly distributed except for on the edges where slightly denser but not forming a conspicuous band; tube 3-4 mm long, 7-8 mm diameter; lobes ovate, 5-5.5 mm diameter, inserted on column ± flush with corolla, yellow pink; each lobe c. 2.5 mm long, 2.5-2.8 mm high, 1.3-1.5 mm wide, outer edge somewhat rounded-obtuse and not upraised above the level of the stylar-head, inner edge acute. Staminal column c. 2 mm long and 2.5 mm diameter; anther appendages lanceolate, c. .8 mm long and 0.5 mm wide; alar fissure c. 1 mm long Style-head c. 1 mm diameter. Pollinaria c. 0.32-0.36 mm long, 0.27-0.32 mm wide, with pellucid germination mouth on outer edge; corpusculum oblong, 0.09-0.11 mm long and 0.05 mm wide. Fruit and seed not seen.
Herbarium Sheets: Bougainville Prov. S. slopes of Crown Prince Range, Apr. 1936, Voyce #D2 (K); Cultivated Emerald Creek ex Mt. Gallego, Guadalcanal, Solomon Is., IML 423 (BRI).
Photo by Ann Wayman, Central Point, Oregon.